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Grassland Restoration Network – Minnesota Style

I am writing this from Moorhead, Minnesota, where our crew is attending the annual Grassland Restoration Network workshop. This year’s workshop is being hosted by The Nature Conservancy’s Bluestem Prairie office and others working on prairie restoration in northwestern Minnesota. We spent most of the first day touring Bluestem Prairie, roughly 6,000 acres owned and managed by the Conservancy. There are some gorgeous prairies here, and they have been doing a lot of restoration work to convert cropland back to prairie in and amongst the remnant prairies. Much of that restoration has been accomplished through contracts with Prairie Restorations Inc. (PRI), a private company that has been doing prairie restoration since the 1970’s. Yesterday evening, we toured the local facilities of PRI and saw their impressive array of equipment and seed production plots.

I’ll write more in the next week or two about what we’re learning here, but for today I’ll just mention one big theme that continues to dominate much of the discussion at these workshops: It’s not the seed harvest or planting that limits our capacity to do good restoration work, it’s the management of invasives after planting. As we’ve visited site after site over the years, that topic has remained at the top of everyone’s concerns.

There are basically two ways the issue manifests itself. First, we tend to rush the restoration process and not prepare the site in a way that will help prevent future weed issues. The worst issues usually occur when we are trying to eliminate existing vegetation other than annual crops. Too often, we don’t spend enough time eliminating the grasses or other invasives – and their seed bank – before planting our prairie vegetation. As a result, new plantings have an abundance of weeds that are difficult to control, especially because they’re now mixed in with the new plants we are trying to establish. Investing in several years of herbicide, disking, fire, and/or other combinations of treatments before planting can help eliminate most of the pre-existing vegetation and greatly improve the quality of new restoration sites.

Surrounded by leadplant in a restored prairie, workshop participants listened to Brian Winter of The Nature Conservancy describe how the site was prepared and planted.

When converting cropland to prairie, many of weed issues have already been dealt with by years of cultivation and weed control, but there are still steps we can take to help deal with potential future invasive species problems. The biggest of those is the elimination of as many invasive species populations around the borders of the restoration site as possible. Investing in the removal of Siberian elm trees, smooth brome, or other nasty plants from field edges can make future weed control efforts much more manageable.

The second major way we get into trouble with invasive species in restoration efforts is that we plant more acres than we can manage weeds on. This often happens because of funding – we get grant money to help pay for restoration work, but that funding usually comes with an aggressive timeline. We commit ourselves to planting a lot of acres quickly and then later realize we’ve just created a massive amount of land that requires invasive species control – which our grant funding doesn’t cover. In some cases we also get into trouble when we start feeling good about our ability to harvest large amounts of seed and figure we should plant as many acres as we can. …and then the weeds show up.

Not all restoration plantings have major invasive species issues, but it’s not always possible to know up front what species are going to be a problem. If bird’s foot trefoil, Siberian elm, or Canada thistle do show up, the best strategy is to get them taken care of when the patches are still small and easy to eliminate. If we’re just dealing with small restored sites, that’s usually feasible. However, when we’re trying to deal with many acres of young restoration plantings and there are small patches of weeds throughout each of them, the problem can become quickly insurmountable.

One of the major management issues at Bluestem prairie is shrub encroachment – especially by willows. They are experimenting with a combination of fire, mowing, and wick application of herbicides. The biggest issue, however, is the number of acres that need treatment. Even if a successful formula for control is developed, it still has to be applied across a very large area.

Invasive species will always be a problem for prairie managers, on both restored and remnant grasslands. However, there are some steps we can take to make our job easier in restored prairies. First, it’s important to take the time to prepare the site ahead of time by eliminating potential invasive problems before planting. Second, regardless of the pressure to move quickly, we have to set the number of acres we restore each year based on our ability to deal with invasive species, not the amount of money or seed we have to do the work.

Ok, time to get back to the workshop. I learned a lot yesterday and hope to learn even more today. Most of all, it’s always inspiring to see how other people are tackling many of the same issues we’re dealing with at home. Even if we can’t provide each other with answers to our thorniest problems, we can at least commiserate about them!

About Chris Helzer

Chris Helzer is the Director of Science for The Nature Conservancy in Nebraska. His main role is to evaluate and capture lessons from the Conservancy’s land management and restoration work and then share those lessons with other landowners – both private and public. In addition, Chris works to raise awareness about the importance of prairies and their conservation through his writing, photography, and presentations to various groups.
Chris is also the author of "The Ecology and Management of Prairies in the Central United States", published by the University of Iowa Press. He lives in Aurora, Nebraska with his wife Kim and their children.

17 thoughts on “Grassland Restoration Network – Minnesota Style”

Fascinating to read about what we are learning about control of invasives. We in Pennsylvania face similar issues, especially when trying to plant native pollinating plants to improve home and business gardens.

Chris,
I am no expert but even here on the coast of Maine we deal with multiple aggressive invasive plants. Since we are frequently just maintaining campsites and beach fronts, we typically use human effort and very targeted herbicide applications. On large tracts for replanting, it would seem the least harmful and most cost effective approach would be controlled burns followed by disking over the course of several seasons. Since the latter is a mechanical solution that lends itself to repeated treatment and large areas, it might make sense to create a weed treated bank of land which you can re-seed when grant funding allows.
Keep us posted on what you learn.

I feel I should relate the following story. In a preserve near my house invasive trees and brush were removed from a moist area. The area was then tilled to prepare it for planting. This area was planted with plugs and probably received seeding too. Although many of the plants introduced as plugs can still be found, the area is now almost completely dominated by Reed Canary Grass.

In contrast, a similar habitat in a nearby forest preserve had brush removed by mowing, but the soil was not disturbed. Where brush was mowed we are seeing some fairly conservative prairie plants resurging (coefficient of conservatism of up to 8) and spot control of Reed Canary Grass has kept this species from dominating.

I think disturbing the soil should be avoided when possible because it appears to set back the development of native plants and leads to a larger problem with invasive species.

Great summary of various environmental and social hurtles. Intense site-prep aside…, I often think about restoration prairies with poor seed compositions as having many vacant seats for community members that are easily infilled with invasive or non-native species. A good example of this would be the lacking component of sedges and native cool season grasses in some prairies, etc. Now, I am aware of the many aggressive exotics that take over despite these efforts, just by shear muscle. One of my interests is in managing birdsfoot trefoil since it seems to have a seed bank resurgence following fire. I’ve started to stake off areas where birdsfoot was treated to ensure that fire will not enter the area until a native grass component thickens. It would be great if you could ask some questions for us regarding empty seats, and how to manage birdsfoot long term. Also, birdsfoot seems to be one of those great hitch-hikers that gets up on mower decks, so folks should be very diligent about blowing off their equipment when mowing on their properties.

Grazing, IMHO, is the best and cheapest way to control so called invasives. Not sure if they are grazing there at PRI, but often times a weed is candy to a cow (or ewe or buffalo). We are having some success grazing out sericea lespedeza here in the Kansas Flint Hills at fairly high stock densities. It is a lot easy to mob graze cows than to spot spray undesirable species in the prairie. And, you can make some money from grazing too!

I was at the meeting also, and as you said, it’s not so much the brush problem itself but the scale of the problem that is so daunting. Fifty or even a hundred acres of brush control is hard enough, but 24,000 acres as at the Glacial Ridge NWR is probably impossible given the size of their problems and the comparatively tiny size of their staff. Thinking well outside the box will be necessary. One thing I pondered while on the ride back today is whether some sort of “conservation homesteading” would be useful, wherein the FWS finds individuals interested in grass based farming (haying, grazing, seed collection) and leases those rights to individuals on a long term basis (thus allowing for the lessee to recoup money for capital investments in livestock and equipment) not for cash but in exchange for control of invasives, wherein the haying and grazing could be integrated with fire management done by the Service. A long term agreement (10 years, 15 years, or an automatic extension if conditions are met) will also help overcome one of the problems that agencies and NGOs have with staff turnover. The staff may turn over, but if lessees are on site long term they can be a source of local knowledge about site conditions and provide some continuity in management approach, of course being guided by current science. It was an excellent meeting though, maybe you can have it down in southern Minnesota some time. Again, excellent blog.

I think impatience, staff turnover, lack of long-term reliable funding (rather than boom-bust cycles), and too few dedicated boots on the ground (paid or volunteer) are the biggest factors limiting success in restoration. Seems like most folks just don’t like the hard work and monotony of a lot of the field work associated with restoration and management. They think their time is better spent doing something “more important”. They forget that to the small critters like those you photograph Chris, their efforts make a world of difference. That’s what they miss. A lot of it has to do with the personalities of the leaders. Why are some CCBs and and NGOs really successful at organizing and conducting restoration and (especially) management work on public and private lands while others are not? I have a hard time believing the only issue is financial resources. Some people just seem to find solutions, others just seem to find excuses. I also think it is a lot to put on the landowner to expect that they as individuals should be able to manage large land areas without occasional help from other organizations. This is especially true for management efforts like prescribed burns. This is something I have the most trouble getting done on a regular basis.

I must tell you that getting out into a preserve to help control invasive species is one of the things I look forward to most in any given week. It can be rather cathartic. I also like to see how much I can accomplish in any given workday and see how the progress has accumulated over time. I am finding I can pull up weeds well over one thousand times in a three hour workday. The number of weeds actually pulled is even higher because I often pull more than one weed with each upstroke of my arm.

Well said Patrick. I have been working in this field for a long time and find that good field workers/practitioners are rare. Many think it is what they want to do until after a few days of doing it. We need more folks like James :-)

Thank you for the recognition. I must defer to a fellow named Kirk Garanflo. He has almost single handedly removed wild parsnip, and other weeds, from a restoration larger than a section (over 640 acres). My contributions seem trivial compared to Kirk’s and the work of other natural area stewards.

I would like to add that I think the impatience Patrick refers to seems to be a folly of youth. Youth seem to be so engaged in finding their place in the world that they often have difficulty being tied down to any one task for long. Also they are in a competitive stage in life where they easily succumb to the pressure of keep pace with peers. In my experience the best people at controlling invasive species are nearing or just beyond retirement age. People in their 50’s, 60’s, 70’s, and even 80’s consistently accomplish more than more athletic high school and college aged young adults.

Davud and James, I think part of what makes a restorationist enjoy the work is precisely having longevity at a site over time, not just to be able to see the progress after a day, but to see the progress over the years, as James mentions. Impatience denies the ability to see the latter and makes it harder to value the former.

Yes, you are right that impatience makes it difficult to value restoration work where results are often not achieved until after many years have passed. Understanding what constitutes reasonable expectations only is achieved through experience. I was incorrect to imply that all youth are impatient. The reason youth consistently appear to be impatient is they do not yet have the experience to understand what constitutes reasonable expectations.